SKU: 68083105834

Holley Terminator X MAX Engine Management Systems 550-929

Sale price$899.98 Regular price$999.98
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Ships within 48 hours · Estimated delivery Jul 25 - Jul 30

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Description

Holley Terminator X MAX Engine Management Systems 550-929Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self learning fuel strategies and the proven, race winning technology of Holley EFI at a budget friendly price! Terminator X Max features real time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and

Take control of your LS engine with Terminator X Max! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley EFI at a budget-friendly price! Terminator X Max features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Part number 550-929 also has Drive-by wire throttle body control. Terminator X Max comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast. The 3.5" touch screen LCD handheld contains an easy to use calibration wizard as well as tuning and gauge display functions. Also included is Holley EFI's industry-leading, easy to use software suite that allows full laptop access for advanced users. Whether you are building a budget beater or a boosted race car, Terminator X MAX has the features and technology you need at a price that won't break the bank!

Features:

  • For GM LS1/LS6 engines with 24x crank reluctor and a Drive-By-Wire Throttle Body, and EV1 Injectors
  • Real-Time fuel map learn, takes the guess work out of tuning your base fuel table.
  • High Impedance Injector Drivers will safely power most Stock LS injectors, and Holley EFI Injectors. Injector support chart provided in the instructions (Will not control Low Impedance Injectors)
  • All of the new Terminator X Max systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control.
  • On-Board 1bar MAP sensor, is perfect for N/A or Nitrous engine combos. If your combination requires a 2+Bar, we recommend GM 12592525, and our adapter part number 558-416.
  • MAP Sensor vacuum hose adapters (1/8th – ¼ and 3/16ths)
  • 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
  • 4 Outputs – Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
  • Boost Control – Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
  • Nitrous Control – Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
  • Advanced Tables – 4x 1D Tables, 1x 1D per Gear Table, 4x 2D Tables, 1x 2D per Gear Table, can be used for any custom tables you can dream up, such as Flex Fuel Sensor Offset Table, or a custom fuel or oil pressure safety!
  • On-Board Diagnostic LEDS for: ECU Power – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allow you to identify any Critical engine issues at a glance
  • The included 3.5" Touchscreen Handheld contains a calibration wizard, that allows you to quickly build a base tune for any LS engine. Additionally the handheld provides internal data-logging and a fully customizable gauge display.
  • The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up!
  • Plug and play compatible with more Holley EFI accessories such as; analog style gauges, shift lights, various modules, and coming soon, 12.3" digital dash support!
  • Free EFI Tuning Software for complete control of your Terminator X power plant
  • Recommended Pedal part number - 10379038
  • Includes: 24x LS Engine Main Harness - EV1 Injector Harness - DBW Throttle Body Harness - Terminator X MAX ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters.

Specs

Brand Holley EFI
Crank Reluctor 24x
Emission Code 3
Ignition Type GM LS 24x
Injector Connector Jetronic / Minitimer (Bosch)
Product Type Terminator X Max LS MPFI
Terminator LS Options Fuel, Spark, Drive-by-Wire
Part Number 550-929
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 68083105834

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Candace McCullough
Waukegan, US
★★★★★ 5
Great chew toy
Color: Blue
I bought this almost a year go. My dog is still chewing on it! Nothing last this long with her. She is a 100lb Rottweiler that is a strong chewer.
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Reviewed in the United States on June 12, 2026
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Dawn Clegg
Carnegie, US
★★★★★ 4
Well loved
Color: Blue, Color: Blue
We just got this sweet girl from the shelter a few days ago. She's had this toy for 2 days and already chomped off one of the legs. She does have other toys so she doesn't play with this one all the time but she does like it a lot! It's very hard and durable on the ends. But as you can see, it's not indestructible. She carries this little guy around the house like they're BFFs. It's super adorable.
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Reviewed in the United States on May 21, 2026
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Michele Johnson
Belleville, US
★★★★★ 5
Indestructible!
These dog chew toys have been a great purchase! My dog loves them and was interested in them right away. The shapes are fun and easy for my dog to hold while chewing, which keeps them entertained for a long time. The material feels durable and has held up really well even with regular chewing. I also like that it helps keep my dog busy and gives them something safe to chew on instead of furniture or shoes. Getting two toys in the pack is a nice bonus, and they seem well made for the price. Overall, I’m very happy with this purchase and would definitely recommend these chew toys to other dog own
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Reviewed in the United States on March 11, 2026
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Deanna Yanda
Battle Creek, US
★★★★★ 5
Indestructible for the heavy chewers in your life!
My dogs can chew anything, and these are still in great shape! Very chew resistant to even my large dogs, and they love them! Easy to wash off if they end up in the food bowl or outside!
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Reviewed in the United States on May 27, 2026
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Annie
Lowell, US
★★★★★ 5
Perfect for aggressive chewers
Super durable and my dog loves it! Keeps her busy and she’s a very aggressive chewer
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Reviewed in the United States on April 4, 2026

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